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%I #20 Nov 21 2022 07:49:52
%S 1,1,1,2,2,1,3,4,6,2,5,1,6,1,1,8,8,2,9,4,3,5,11,2,20,2,9,3,14,1,15,16,
%T 5,8,1,12,18,3,3,8,20,1,21,5,4,11,23,4,14,20,4,12,26,3,5,1,9,14,29,2,
%U 30,5,9,32,4,5,33,16,11,1,35,8,36,6,10,9,5,1
%N a(n) = denominator of (sigma(n) / phi(n)).
%C a(n) = 1 for numbers in A020492 (balanced numbers).
%H Amiram Eldar, <a href="/A289412/b289412.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) = denominator of (A000203(n) / A000010(n)).
%e For n = 7, sigma(7) / phi(7) = 8/6 = 4/3, a(n) = 3.
%t Array[Denominator[DivisorSigma[1, #]/EulerPhi[#]] &, 78] (* _Michael De Vlieger_, Aug 19 2017 *)
%o (Magma) [Denominator(SumOfDivisors(n) / EulerPhi(n)): n in[1..1000]]
%o (PARI) a(n) = denominator(sigma(n)/eulerphi(n)); \\ _Michel Marcus_, Aug 21 2017
%Y Cf. A289336 (numerators).
%Y Cf. A000010, A000203, A018894, A020492, A023897, A055234, A070032, A070033.
%K nonn,frac
%O 1,4
%A _Jaroslav Krizek_, Aug 19 2017
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